Amongst the following, identify the condensation polymer/s:(A) Bakeli…

The correct answer is Option (2) → (A), (C) and (D) only

Condensation polymers are formed by repeated condensation between bi- or tri-functional monomers, with loss of a small molecule such as \( \ce{H2O} \), HCl or an alcohol at each step. Addition polymers are formed by repeated addition of monomers with a double bond, without loss of any molecule.

• (A) Bakelite — Condensation polymer. Phenol and formaldehyde first give o- and p-hydroxymethylphenol; these condense with more phenol, losing water at each step, to give novolac, which is cross-linked into bakelite.

      \( \ce{C6H5OH + HCHO -> HOC6H4CH2OH} \)

      \( \ce{HOC6H4CH2OH + C6H5OH -> HOC6H4-CH2-C6H4OH + H2O} \)

• (B) Teflon — Addition polymer. Tetrafluoroethene molecules add on to one another; no small molecule is lost.

      \( n\,\ce{CF2=CF2} \xrightarrow[\text{high pressure}]{\text{catalyst}} \ce{-(CF2-CF2)_{n}-} \)

• (C) Melamine formaldehyde resin — Condensation polymer. Melamine and formaldehyde condense with loss of water.

      \( \text{melamine} + \ce{HCHO} \rightarrow \text{melamine-formaldehyde polymer} + \ce{H2O} \)

• (D) Nylon-2–nylon-6 — Condensation polymer. An alternating copolymer of glycine and aminocaproic acid, joined by amide bonds with loss of water; it is a biodegradable polyamide.

      \( n\,\ce{H2N-CH2-COOH} + n\,\ce{H2N-(CH2)5-COOH} \rightarrow \ce{-[NH-CH2-CO-NH-(CH2)5-CO]_{n}-} + (2n-1)\,\ce{H2O} \)

• (E) Buna-S — Addition polymer. A copolymer of buta-1,3-diene and styrene formed by addition.

      \( n\,\ce{CH2=CH-CH=CH2} + n\,\ce{C6H5CH=CH2} \rightarrow \ce{-(CH2-CH=CH-CH2-CH(C6H5)-CH2)_{n}-} \)

Note: This question is from the pre-rationalised NCERT book (2022-23). The topic is not there in the latest NCERT book (2026-27), and it is also out of the CUET 2026 syllabus.

NCERT (Pre-rationalised edition, 2022-23):
Condensation Polymers

Nylon 2–Nylon 6